A fabrication process using acidic ethanol/water as a medium was developed to achieve homogenous dispersion of chitin nanofibrils (ChNFs) in a chitin propionate (CP) solution to form ChNF-reinforced CP nanocomposites. CP was prepared by propionylation of chitin to improve its dissolution in green organic solvents. ChNFs were extracted from chitin via partial alkali deacetylation in water. An acidified ethanol/water mixture as a medium was found to dissolve CP and disperse ChNF suspensions simultaneously, forming clear and stable formulations. The degree of ChNF dispersion and compatibility between ChNF and CP in the acidified ethanol/water mixture yielded transparent ChNF-reinforced CP nanocomposites with a moderate UV-blocking capability of up to 76%. The tensile strength and modulus of 15% ChNF-filled nanocomposites were enhanced by 66 and 97%, respectively, when compared to the neat films. In addition, the maximum degradation temperature was increased by 40 °C. The increase in storage modulus was more pronounced above the glass transition temperature. These results demonstrated that ChNFs had substantial reinforcing effects on the cast CP nanocomposites.

中文翻译：

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酸性乙醇/水铸造法改善几丁质纳米原纤维的分散性和丙酰化几丁质生物复合材料的性能

开发了一种使用酸性乙醇/水作为介质的制造工艺，以实现几丁质纳米纤维（ChNF）在几丁质丙酸酯（CP）溶液中的均匀分散，从而形成ChNF增强的CP纳米复合材料。CP是通过甲壳质的丙酰化制备的，以改善其在绿色有机溶剂中的溶解度。通过在水中部分碱脱乙酰从几丁质中提取ChNFs。发现以酸化的乙醇/水混合物为介质可同时溶解CP和分散ChNF悬浮液，从而形成清晰稳定的制剂。在酸化的乙醇/水混合物中，ChNF的分散程度和ChNF与CP之间的相容性产生了透明的ChNF增强的CP纳米复合材料，具有中等的紫外线阻隔能力，最高可达76％。15％ChNF填充的纳米复合材料的拉伸强度和模量分别提高了66％和97％，与整齐的胶片相比。此外，最高降解温度提高了40°C。高于玻璃化转变温度，储能模量的增加更为明显。这些结果表明，ChNFs对铸造的CP纳米复合材料具有实质性的增强作用。